Income Taxes - Schedule of Income Tax Expense and Effective Tax Rate (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Income Tax Disclosure [Abstract]
Income tax expense	$ 20.6	$ 20.0	$ 61.0	$ 65.9
Effective tax rate percentage	24.10%	26.00%	43.90%	25.80%

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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